Ingenious Design of Tube-11 Double Tube Vibrating Rod Level Switch

“Vibrating level switches are mostly used to control and detect solid particles or powdered materials in silos or containers, and are especially suitable for materials that are easy to form hanging materials, materials that are clamped, and materials with poor fluidity.

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Vibrating level switches are mostly used to control and detect solid particles or powdered materials in silos or containers, and are especially suitable for materials that are easy to form hanging materials, materials that are clamped, and materials with poor fluidity.

At present, there is a vibrating material level detection device abroad (as shown in Figure 1). In order to make the inner and outer vibrating bodies work at the same resonant frequency, a mass block that can move along the longitudinal direction of the vibrating body is arranged on the inner vibrating body. As an adjustment body, the position of the mass block changes the mass distribution of the inner vibrating body, thereby changing the free resonance frequency of the inner vibrating body. It resonates most strongly with the inner vibrator.

figure 1

The prerequisite for the mass block to function is to ensure that the connection between the mass block and the inner vibrating body has sufficient rigidity. In order to realize the rigid connection, the lower end of the mass block is provided with an elastic opening, and the elastic force of the elastic opening is ensured enough. When the vibrating material level detection device is installed and debugged the position of the mass block, a small screwdriver is used from the upper end of the material level device to pass through the central opening of the piezoelectric component and the central hole of the vibrating body transition device at the same time, and extend into the inner vibrating body to measure the mass. The block is rotated to debug its position.

However, this structure has the following problems:

1. It needs to pass through the center hole of the piezoelectric component and the center hole of the vibrating body transition device from the upper end to debug the position of the mass block. The screwdriver is required to have a small diameter and a long length. Because the lower end of the mass block is provided with an elastic opening, it is in a relaxed state. The outer diameter is larger than the inner diameter of the inner cavity of the inner vibrating body, and at the same time, in order to achieve a rigid connection, the elastic force of the elastic opening is large, which makes the torque requirement of the screwdriver to rotate the mass block very large, and it is extremely difficult or even impossible to rotate;

2. Since the elastic opening is located at the lower end of the mass block, the moving direction of the mass block can only move in one direction from bottom to top. This is because the outer diameter of the lower end of the mass block is larger than the inner diameter of the inner cavity of the inner vibrating body in the relaxed state. If the mass block moves downward, one end of the elastic opening will generate a larger frictional force with the inner cavity of the inner vibrating body, so that the elastic opening is further enlarged and completely Obstructing the movement of the mass block, it can be seen that the mass block cannot be adjusted flexibly in both directions. Once the one-way adjustment position of the mass block exceeds the normal position, it cannot be reversibly returned, resulting in waste.

On the basis of many tests, the R&D engineer of Shenzhen Jiwei Automation Technology Co., Ltd. has improved the structure of the existing double-tube vibrating rod level switch (as shown in Figure 2). The mass block is screwed into the vibrating inner tube. The grooves or protrusions on the expansion part of the mass block can cooperate with other components to rotate the mass block, so as to adjust the position of the mass block in the vibrating inner tube. When the expansion bolt is screwed into a certain depth relative to the mass block, the expansion part on the mass block can be opened, so that the rigid connection between the mass block and the vibration inner tube can be easily realized. Before expansion, the mass block is screwed with the inner thread of the vibrating inner tube through the outer thread, so the mass block can easily realize bidirectional reversible arbitrary debugging in the vibrating inner tube.

figure 2

Practice has proved that the improvement can not only realize the two-way debugging of the mass block, but also the debugging process becomes simpler, the efficiency is higher, and the product quality is more stable and reliable. Jiwei Automation successfully applied for an invention patent for the design.